ath6kl: Support for TCP checksum offload to firmware

The change enables offloading TCP checksum calculation to firmware.
There are still some issues with the checksum offload so better to
disable it by default until the issues are resolved.

To enable TCP checksum offload for tx and rx paths, use
the ethtool as follows:
ethtool -K <interface> tx on
ethtool -K <interface> rx on

To disable TCP checksum offload, for tx and rx paths, use
the ethtool as follows:
ethtool -K <interface> tx off
ethtool -K <interface> rx off

kvalo: indentation changes

Signed-off-by: Rishi Panjwani <rpanjwan@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

1 files changed, 34 insertions, 4 deletions

diff --git a/drivers/net/wireless/ath/ath6kl/txrx.c b/drivers/net/wireless/ath/ath6kl/txrx.c
index 506a303..78bd573 100644
--- a/drivers/net/wireless/ath/ath6kl/txrx.c
+++ b/drivers/net/wireless/ath/ath6kl/txrx.c
@@ -244,6 +244,10 @@ int ath6kl_data_tx(struct sk_buff *skb, struct net_device *dev)
 	u8 ac = 99 ; /* initialize to unmapped ac */
 	bool chk_adhoc_ps_mapping = false, more_data = false;
 	int ret;
+	struct wmi_tx_meta_v2 meta_v2;
+	void *meta;
+	u8 csum_start = 0, csum_dest = 0, csum = skb->ip_summed;
+	u8 meta_ver = 0;
 
 	ath6kl_dbg(ATH6KL_DBG_WLAN_TX,
 		   "%s: skb=0x%p, data=0x%p, len=0x%x\n", __func__,
@@ -265,6 +269,14 @@ int ath6kl_data_tx(struct sk_buff *skb, struct net_device *dev)
 	}
 
 	if (test_bit(WMI_ENABLED, &ar->flag)) {
+		if ((dev->features & NETIF_F_IP_CSUM) &&
+				(csum == CHECKSUM_PARTIAL)) {
+			csum_start = skb->csum_start -
+					(skb_network_header(skb) - skb->head) +
+					sizeof(struct ath6kl_llc_snap_hdr);
+			csum_dest = skb->csum_offset + csum_start;
+		}
+
 		if (skb_headroom(skb) < dev->needed_headroom) {
 			struct sk_buff *tmp_skb = skb;
 
@@ -281,10 +293,28 @@ int ath6kl_data_tx(struct sk_buff *skb, struct net_device *dev)
 			goto fail_tx;
 		}
 
-		if (ath6kl_wmi_data_hdr_add(ar->wmi, skb, DATA_MSGTYPE,
-					    more_data, 0, 0, NULL,
-					    vif->fw_vif_idx)) {
-			ath6kl_err("wmi_data_hdr_add failed\n");
+		if ((dev->features & NETIF_F_IP_CSUM) &&
+				(csum == CHECKSUM_PARTIAL)) {
+			meta_v2.csum_start = csum_start;
+			meta_v2.csum_dest = csum_dest;
+
+			/* instruct target to calculate checksum */
+			meta_v2.csum_flags = WMI_META_V2_FLAG_CSUM_OFFLOAD;
+			meta_ver = WMI_META_VERSION_2;
+			meta = &meta_v2;
+		} else {
+			meta_ver = 0;
+			meta = NULL;
+		}
+
+		ret = ath6kl_wmi_data_hdr_add(ar->wmi, skb,
+				DATA_MSGTYPE, more_data, 0,
+				meta_ver,
+				meta, vif->fw_vif_idx);
+
+		if (ret) {
+			ath6kl_warn("failed to add wmi data header:%d\n"
+				, ret);
 			goto fail_tx;
 		}